Electromagnetic relay



April 6, 1954 E. E. FRANZ 2,674,671

ELECTROMAGNETIC RELAY Filed Sept. 12, 1951 4 Sheets-Sheet 1 IN VENTOR E. E. mA/VZ Arm/WU April 6, 1954 E. E. FRANZ ELECTROMAGNETIC RELAY Filed Sept. 12, 1951 4 Sheets-Sheet 2 M6 No JNVENI'OR E. E. FRANZ W AT7LR'NEV April 6, 1954 E. E. FRANZ ELECTROMAGNETIC RELAY 4 Sheets-Sheet 5 Filed Sept. 12, 1951 INVENTOR E. E. F RA NZ ATTORNEY April 6, 1954 E. E. FRANZ ELECTROMAGNETIC RELAY 4 Sheets-Sheet 4 Filed Sept. 12, 1951 wm/mn E. E. FRANZ ATAE I i Patented Apr. 6, 1954 UNITED STATES PATENT OFFICE ELE CTROMAGNETIC RELAY Application September 12, 1951, Serial No. 246,191

8 Claims. 1

This invention relates to electrical switches and more particularly to those of the relay type.

Most of the commercially known types of electrical relays are composed of groups of contact springs arranged so that upon actuation of the armature during energization of the relay coil, the contact springs will be actuated to open normally closed contacts and. to close normally open contacts. The contact springs when assembled initially require accurate adjustments. They frequently become distributed during handling. After they are mounted in their respective equipments, other adjustments are necessary to assure proper functioning. It is, therefore, not unusual for the commercially known types of relays to become defective or ineflicient due to wear and disturbances of the spring contacts. Furthermore, foreign bodies as dust and metal chips, in storage and operation, impair their functioning. Wear does likewise and they cannot be used in explosive atmospheres because arcing results when breaking a circuit.

An object of the present invention is to provide an electrical switch which is simple in structure, efficient in operation and wherein the switch closing elements are not subject to wear, mechanical disturbances, foreign bodies nor arcing.

With this and other objects in view, the invention comprises an electrical switch having spaced contacts with a pool of mercury interposed between the contacts and an element movable into the mercury causing it to flow outwardly to close the contacts electrically.

Although the switch unit may be employed singly, it is readily adaptable for assembly wherein any selected number of the switch units may be employed to function as multiple switch or as a relay. The juxtaposed pools of mercury in the units have permanent magnetic elements aiiected by an externally related permanent magnet called armature or actuator, causing the elements in the normally open units to float on their pools of mercury while the elements in the normally closed units are attracted by the armature to spread the mercury into electrical engagement with the contacts. This normal action of the armature is the result of positioning one pole thereof adjacent the units. Movement of the armature through energization of a magnetic coil may cause the units to operate simultaneously or sequentially depending upon the contour of the armature to open the normally closed contacts and to close the normally open contacts.

Other objects and advantages will be apparent from the following detailed description when considered in conjunction with the accompanying drawings wherein:

Fig. l is an enlarged isometric view of the switch, portions thereof being broken away;

Fig. 2 is a side elevational view of the switch with the front terminal units removed;

Fig. 3 is a lateral sectional view of the switch illustrating one of the switch units mounted in the holder;

Fig. 4 is a top plan view of the switch unit;

Fig. 5 is a lateral sectional View taken along the line 5--5 of Fig. 3;

Fig. 6 is a lateral sectional view of the entire switch;

Figs. '7, 8, 9 and 10 are isometric views of termi nal units mounted in groups on the support;

Figure 11 is an enlarged fragmentary sectional View illustrating one of the supporting springs for the fulcrum of the magnet armature;

Fig. 12 is a fragmentary detailed View of the armature mounting means; and

Figs. 13 and 14 are views of different types of magnet armatures.

Referring now to the drawings, attention is first directed to Figs. 3, 4 and 5 which illustrate the individual switch units. The illustration of the switch unit in these figures is many times larger than the actual unit. The switch unit indicated generally at 2B is initially formed of a glass stem portion 25 having aligned tubular portions 22 and .23 and laterally extending portions M. This entire structure is formed or glass and during the initial forming steps the portions 24 are heated sufficiently to allow contact wires 25 to be embedded and sealed therein in the conventional manner.

A glass container 2?, substantially elliptical in cross section, has its lower end formed as illustrated in Fig. 3 to provide end pockets it and a central pocket 22. The stem assembly is placed in the open end of the receptacle and fused there-- to so that subsequently the entire structure may be exhausted prior to sealing the upper portion of the tube 22. Prior to the exhausting and sealing operation, a quantity of mercury is placed into the container 21 so that pcols of mercury 3!? thereof will partially fill the pockets 28 surrounding the inner ends of the contacts 25 and a pool 3! of mercury will fill the pocket 29.

An element 33 of suitable material is dropped into the tubular portions 22 and 23 of the unit 29 after which the unit may be exhausted and the tubular portion 22 sealed in the conventional manner. The element 33 in the present embodiment of the invention is cut from a length of wire of magnetizable material. In the final structure, certain of the units will function as normally closed switches, While others will function as normally open switches. In view of this fact, therefore, the elements 33 of a number of switch units 20 will be magnetized so that their north poles will be up and their south poles down while another grou of elements 33 will be magnetized so that their poles will be reversed.

A holder 35 of the contour shown in Figs. 1 and 2 is provided with an end portion 35 crossshaped in general contour and a central portion 31 with a plurality of apertures 38 (Fig. 3) therein to receive the individual switch units 20. The outer portions 43 of the contact wires 25 extend in opposite directions about the holder 35. Vertical grooves 4! are provided in the sides of the central portion 31 to locate the outer contact portions 40 at given positions relative to each other. The extreme outer ends of the contacts may be secured at 42 by suitable means to the under-surface of the holder.

1n the present embodiment of the invention a permanent magnet armature or actuator 45, V-shaped in cross-section, has its poles 45 and 41 (Fig. 6) disposed substantially parallel with each other. A fulcrum knife bar All for th armature is diamond-shaped in cross-section and extends longitudinally of the holder 35 between its cross-shaped end 35 and a coil supporting end 49. Projections 50 adjacent the inner surfaces of each end of the holder 35 have inverted V-shaped recesses 51 in their under-surfaces to receive the fulcrum bar 48. Anchoring spring clips 52 of the contour shown in 11 have inwardly projecting ends 53 to rest on shoulders of the projections 50 to hold each end of the fulcrum against displacement.

Triangular portions 55 formed on the ends of the armature 45 cooperate with the ends of the fulcrum bar 48 by engaging spring rings 51 as shown in Fig. 12 to keep the armature in engagement with the fulcrum. It will be noted by viewing Fig. 12 that the under-surface of the armature, including the portions 55, is grooved longitudinally at 58 to rest upon the upper edge of the fulcrum and to rock thereon when moved from one position to another. The connecting rings 51 are of the contour shown in Fig. 12, they being recessed at 59 to receive the portions 55 of the armatur and the lower edge of the fulcrum 58. The rings 51 are intially deflected in assembly and this force tends to urge the armature 45, Fig. 12, counterclockwise. against a stop 50. This eccentric loading exists even when the armature is moved against stop 6|, Fig. 6.

The permanent magnet armature 45 shown in Figs. 1, 2, 6 and 12 is of the straight slot type whereby the magnetic elements 33 in all of the switch units 29 will be affected simultaneouly due to the positioning of poles 45 and 41 relative to the units. The slots in th magnet armature may be of various other contours as illustrated. in Figs. 13 and 14 whereby the switch units may be operated in any desired sequence. In Fig. 13 the annature 62 has opposing pole members 63 and 64 divided by a spiral slot 65 which would cause the switch units to operate successively. The armature 61 shown in Fig. 14 has spaced pole members 58 and 69 separated by a reverse spiral groove 10. This type of armature would cause the switch units to operate in pairs successively from the outermost units to the central units. Other forms of armature slots may be employed to accomplish different operating cycles of the switch units.

An electromagnetic unit 10 has a mounting member 1| secured to the adjacent end of th holder 31. The unit 10 includes a coil portion 12 composed of one or more operating windings. In the present embodiment of the invention, two reversely wound coils are disposed in the coil unit with their lead wires connected to terminals 13 which extend through th member 1| and the upper portion of the cross-shaped end.

36. The unit 10 is provided with. a substantially U-shaped core 15, one leg 16 of which extends centrally through the coil unit 12 and is positioned adjacent the magnet armature 45. The other leg 11 of the core extends externally of the coil unit with its outer end 18 spaced from the end 16 adjacent the magnet armature 45.

A plurality of terminal units 8D, 81, 82, and. 83, are shown respectively in Figs. 7, 8, 9 and 10. These terminal units include conductive elements which may be similar inv contour except that they may vary in length. The conductive elements in the present embodiment of the invention are substantially L-shaped in general contour, molded in holders 85 of dielectric material so that their inner or laterally extending portions 81 may be disposed at varied positions to engage their respective contact wires 40 of the switch units 20. Apertures 88 formed in the dielectric elements 86 permit securing of the terminal units to the holder 31. Recesses 89 in the terminal units receive the adjacent crossmembers of the end 36 of the holder while apertures 90 permit access to the portions 81 which may be bent into engagement with their respective contacts 40 of the switch units 23. With this arrangement, depending upon the relative positioning of the groups, terminal units mounted on each side of the holder 31, numerous circuits may be controlled either simultaneously or in a given sequence. The circuits to be controlled may be connected to their respective switch units through the terminals 35. The control circuits for the coil unit 12 are connected to the terminals 13 protruding through slots 36 in the relay head and extending back through mounting member 1| to the coil leads.

Considering now the operation of the switch, attention is first directed to Fig. 6. If only one switch unit is employed and this switch unit should include normally open contacts 25, the position of the armature 45 indicates that the pole 46 thereof repels the magnetic element 33 assisting it to float on the pool of mercury 3|. Movement of the armature 45 to move the pole 46 away from the element 33 and move the pole 41 into general alignment with the element will cause closing of the contacts 25 electrically, resulting from the pole 41 attracting the element 33, causing the mercury 3| in the pocket 29, Fig. 3, to overflow and join the pools 30 of mercury in the pockets 28. If preferred, there may be only one pocket and one pool of mercury, the inner ends of the contacts 25 being normally free of the pool but closed electrically by the pool of mercury when the magnetic element 33 is forced into the pool attracted by the armature 45. However, by submerging the ends of the contacts 25 in their. individual pools of mercury and joining these. pools together by displacement of the central poolby the element 33, the deleterious effects ofarcingduring the breaking of the contacts is eliminated.

The evacuation of the glass container or filling it with inert gas will further this advantage.

' In the present embodiment of the invention thirty-two switch units are employed and under the control of the magnet armature 45. This armature has two positions, the normal po 'sition shown in solid lines in Fig. 6 and the operated position shown in dotted lines in this figure. The armature may be biased to normal position by a spring or other suitable means in which case only a single operating winding is required. In some cases, however, it may be desirable to have the armature under magnetic control and to move it from one position to another by reversing the polarity of the core ends 16 and 18 with two windings or by reversing the current in a single winding. The ends 16 and It of the core 75 are positioned out of direct alignment with the poles 46 and 41 of the armature 45 so that they will create pushing and pulling effects on the poles of second coil of the unit 12 will reverse the polarity 3 of the ends '16 and l'8 to repel the poles of the armature 45, causing rocking movement thereof to bring the pole member 41 into general alignment with the magnetic elements 33. The core member 18 serves a double function in that it not only repels the pole member 46 in this instance but attracts pole member 41. During the energization in the second coil, all of the switch units, which are normally open, will close by the magnetic elements being drawn into their pools of mercury, causing the three pools of mercury to unite, connecting the contacts electrically. Furthermore, the normally closed switch units or contacts will be opened by the pole member 47 of the armature repelling the magnetic elements of those switch units. It will be apparent that the deenergization of the second coil and the energization of the first coil, will return the entire series of switch units to their original condition by returning the armature from the dotted line position shown in Fig. 6 to the solid line position shown therein. Here again the portion it of the core for the electromagnetic unit tends to repel the pole member 41 while at the same time it attracts the pole member 46 thereof, the core member 16 assisting in attracting the pole member 61 moving the armature against the stop 95.

With this type of switch structure, which may be composed of a single switch unit or any desired number of switch units, it will be apparent that the circuit opening and closing elements thereof will never require adjustment, that the contacts will never be disturbed to affect their efficiencies, and regardless of how long these switch units may be employed, they will always be efficient. If preferred, the individual switch units may be shielded in any suitable manner. Although the structure shown in the drawings appears to be extremely large as compared to the commercial types of relays, for example, this entire structure may be made to require no more panel mounting space than the conventional spring pileup type relays and since the contact units may be very small and closely spaced, a

large number of them can be mounted in a structure of moderate length.

It is to be understood that the above described arrangements are simply illustrative of the application or" the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. An electrical relay switch comprising a series of individual units each including a hermetically sealed container having a pocket with a pool of mercury spaced from the inner ends of contacts sealed in the container, and a magnetic element floating on the pool of mercury, a holder for supporting the series of units in general alignment with each other, and a magnetic armature movable relative to all the units and formed of a given contour to cause actuation of the magnetic elements in a given order to cause the pools of mercury to flow outwardly to connect the contacts electrically.

2. An electrical relay switch comprising a series of individual units eash including a hermetically sealed container having a pocket with a pool of mercury spaced from the inner ends of contacts sealed in the container, and a magnetic element floating on the pool of mercury, a holder for supporting the series of units in general alignment with each other, and a permanent magnet armature normally disposed with one of its poles adjacent the magnetic elements whereby certain of the magnetic elements with normally open contacts will be repelled and the other elements will be attracted to cause their pools of mercury to normally close the contacts electrically.

3. An electrical reiay switch comprising a series of individual units each including a hermetically sealed container having a pocket with a pool of mercury spaced from the inner ends of contacts sealed in the container, and a magnetic element floating on the pool of mercury, a holder for supporting the series of units in general alignment with each other, and a permanent magnet armature normally disposed with one of its poles adjacent the magnetic elements whereby certain of the magnetic elements with normally open contacts will be repelled and the other elements will be attracted to cause their pools of mercury to normally close the contacts electrically, and means energizable to move the magnet armature to position its other pole adjacent the units to reverse the actions on the magnetic elements to close the normally open contacts and open the normally closed contacts.

4. An electrical relay switch comprising a series of individual units each including a hermetically sealed container having a pocket with a pool of mercury spaced from the inner ends of contacts sealed in the container, and a magnetic element floating on the pool of mercury, a holder for supporting the series of units in general alignment with each other, and a permanent magnet armature normally disposed with one of its poles adjacent the magnetic elements whereby certain of the magnetic elements with normally open contacts will be repelled and the other elements will be attracted to cause their pools of mercury to normally close the contacts electrically, and an electromagnetic unit including a substantially u shaped core with its polar ends disposed adjacent the poles of the armature and reversely wound coils whereby energization of the coils alternately will cause reversing of the polarity oi the ends of the core to move the armature to reverse the actions of the magnetic elements to open electrically the normally closed contacts and close electrically the normally open contacts.

5. An electrical relay switch comprising a series of individual units each including a hermetically sealed container having pockets for pools of mercury, contacts with their inner ends submerged in their respective pools of mercury, and a magnetic element floating on the remaining pools of mercury, and a magnet armature movable into positions to alternately align the poles thereof with the magnetic elements to affect the magnetic elements whereby certain of the magnetic elements will be repelled and others attracted to cause their pools of mercury to overflow and electrically contact their other pools.

6. An electrical relay switch comprising a series of individual units each including a hermetically sealed container having pockets for pools of mercury, contacts with their inner ends submerged in their respective pools of mercury, and a magnetic element floating on the remaining pool of mercury, and a magnet armature movable into positions to alternately align the poles thereof with the magnetic elements to aflect the mag netic elements whereby certain of the magnetic elements will be repelled and others attracted to cause their pools of mercury to overflow and electrically contact their other 130015, and electromagnetic coils energizable alternately to cause movement of the magnet armature.

7. An electrical relay switch comprising a series of individual units each including a hermetically sealed container having a pocket with a pool of mercury spaced from the inner ends of contacts sealed in the container, and a magnetic element floating on the pool of mercury, a holder for supporting the series of units in general alignment with each other, and a movable magnetic armature having pole pieces of given contours to cause actuation of the magnetic elements in a predetermined sequence to cause opening and closing of the contacts electrically by repelling the magnetic elements and attracting the magnetic elements into their pools of mercury to cause them to overflow and electrically engage their other pools including the contacts.

8. An electrical relay switch comprising a series of individual units each including a hermetically sealed container having a pocket with a pool of mercury spaced from the inner ends of contacts sealed in the container, and a magnetic element floating on the pool of mercury, a holder for supporting the series of units in general alignment with each other, a holder for the series of units, terminals mounted on the holder and electrically engaging their respective contacts, and a permanent magnet armature normally disposed with one of its poles adjacent the magnetic elements whereby certain of the magnetic elements with normally open contacts will be repelled and the other elements will be attracted to cause their pools of mercury to normally close the contacts electrically, and an electromagnetic coil unit supported by the holder and having reversely wound coils and legs of a substantially U-shaped core disposed adjacent the poles of the armature to alternately move the armature from one position to another upon alternate energization of the coils.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,010,620 Crumpton Dec. 5, 1911 1,642,932 McCabe Sept. 20, 1927 1,653,283 Hood Dec. 20, 1927 2,166,163 Larson July 18, 1939 2,292,371 Ferrell Aug. 11, 1942 

